[cncuser1]

For my limit switches and touch probe I plan to use shielded wire.
The shielding is a foil type of shielding that is in contact with an uninsulated wire.

To that is this shielding connected? Mains ground, PC ground ( via the breakout board) or not connected to anything?

[mactec54]

For my limit switches and touch probe I plan to use shielded wire.
The shielding is a foil type of shielding that is in contact with an uninsulated wire.

To that is this shielding connected? Mains ground, PC ground ( via the breakout board) or not connected to anything?

Mains Ground and
only one end should be connected or you will have problems

[Al_The_Man]

To that is this shielding connected? Mains ground, PC ground ( via the breakout board) or not connected to anything?

The mains ground and PC ground is usually the same thing as the PC power supply has a ground to PC chassis and the switching supply common is generally connected to the ground plane of the MB which in most cases has at least one grounding screw through to case.
There has been many previous posts here on grounding which will expand on this if you do a search.
It pays to set up a common ground plate or bus for all grounds.
Al.